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BUG: KASAN: stack-out-of-bounds in should_fault_in_pages fs/gfs2/file.c:785 [inline]
BUG: KASAN: stack-out-of-bounds in gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070
Read of size 8 at addr ffffc900032cfd50 by task syz.4.237/5426

CPU: 1 PID: 5426 Comm: syz.4.237 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 should_fault_in_pages fs/gfs2/file.c:785 [inline]
 gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070
 gfs2_file_write_iter+0x467/0x11d0 fs/gfs2/file.c:1166
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe58fd0dec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe58df33038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe58ff65180 RCX: 00007fe58fd0dec9
RDX: 00000000000000a0 RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007fe58fd90f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe58ff65218 R14: 00007fe58ff65180 R15: 00007ffd9fc2eb08
 </TASK>


addr ffffc900032cfd50 is located in stack of task syz.4.237/5426 at offset 48 in frame:
 vfs_write+0x0/0xd00

this frame has 3 objects:
 [32, 48) 'iov.i'
 [64, 112) 'kiocb.i'
 [144, 184) 'iter.i'

Memory state around the buggy address:
 ffffc900032cfc00: f1 f1 f1 f1 00 00 00 00 00 00 00 f3 f3 f3 f3 f3
 ffffc900032cfc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900032cfd00: 00 00 00 00 f1 f1 f1 f1 00 00 f2 f2 00 00 00 00
                                                 ^
 ffffc900032cfd80: 00 00 f2 f2 f2 f2 00 00 00 00 00 f3 f3 f3 f3 f3
 ffffc900032cfe00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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